Adoptive cell therapy (ACT) using tumor infiltrating lymphocytes (TIL) or cells that have been genetically engineered to express an anti-cancer antigen T cell receptor (TCR) can produce positive clinical responses in some cancer patients. Nevertheless, obstacles to the successful use of ACT for the widespread treatment of cancer and other diseases remain. For example, T cells and TCRs that specifically recognize cancer antigens may be difficult to identify and/or isolate from a patient. Accordingly, there is a need for improved methods of obtaining cancer-reactive T cells and TCRs.